The invention refers to a guardrail for roads.
Various types of guardrails are known, both of metal and of concrete. In particular, a widely used guardrail has a longitudinal rail made of sheet metal with a curved profile, fixed at intervals to posts set in the ground, and placed at a height of about 50 cm, substantially corresponding to the height of the center of gravity of the passenger vehicles generally in use. The functions of guardrails are to keep a vehicle that hits them inside the carriageway, to prevent it as far as possible from assuming attitudes that would be dangerous for the passengers or for other vehicles and to absorb as much of the force of the impact of the vehicle as possible. Although guardrails of the most recent known types represent a considerable improvement with respect to the earlier ones, there is nevertheless always a tendency in the field to improve this product for safety purposes.
An aim of the present application is to obtain an improved performance from guardrails as far as safety is concerned, for both heavy and light vehicles.
More precisely the aim is to create a guardrail that is able to absorb high impact forces, for example when struck by a heavy vehicle such as a truck or the like, and that is able to keep the vehicle on the carriageway in such an attitude as to minimize any injury to the occupants.
A further aim is to create such a guardrail that can be produced at an economically acceptable cost.
A further aim is to create such a barrier that is highly durable.
These aims have been achieved with the guardrail as defined in the following detailed description.
More particularly, the guardrail of the invention comprises, on vertical uprights or posts, fixed in the ground and spaced apart, a longitudinal rail formed by a pair of sheet metal strips with a double-wave profile arranged specularly to each other and connected at intervals by steel ribs or brackets, the longitudinal rail being supported on the uprights by means of deformable spacers. In some variants the guardrail can be made with further continuous horizontal elements fixed to uprights over the longitudinal rail and set at a distance therefrom. The spacer can possibly be made with side flanges, so that as it is deformed against the upright, it can enfold it and prevent undesirable crosswise shifting between the upright and the longitudinal rail.
The strips and the ribs are preferably made of COR-TEN steel. The new barrier is able to absorb high impact forces. It is also able to keep vehicles on the road, even high, heavy vehicles, allowing a certain amount of rolling but preventing overturning. It is durable. Lastly, it allows drivers a good view because any longitudinal elements have a reduced height.